If we cannot step into the same river twice, can we address the same person twice? Yes. And no.
Amazingly, compared to the human, the vast and infinite universe seems straight-forward and easy to understand (should we have the intelligence to contain it). The human, on the other hand, is by its nature a bundle of irreconcilable contradictions.
The human has attempted to fix itself as a static reality. The "I" to which I refer today is understood to be the same "I" that it was yesterday. Similarly, the "you" to whom I refer today is understood to be the same "you" to whom I referred yesterday. And in some sense these identities must indeed have some form of continuity.
Yet we are ever changing. And in the context of this reality we understand that the continuity of identity is merely 'formal'; it is an artificial construct whereby we are able to 'know' things.
As individual selves we have reified ourselves, believing ourselves to be fixed entities. Consequent to this we have established patterns of behavior which define ourselves, to ourselves and to others. In this, we are able to address each other and respond to one another as someone known. I know myself. You know me. I know you.
Yet we are ever changing. How then do we say we 'know' someone else? We both know them and do not know them. And it is in this ambiguity that we learn something of the art of acceptance and tolerance. It is in this ambiguity that we learn openness.
Should we wish to assign judgments upon others we must do so realizing that we are shooting at a moving target as if it were fixed; we are necessarily speaking to the past, not the present moment. Admittedly, we are typically locked into a specific set of behaviors, and from a purely empirical point of view we can generally predict the continuity of these behaviors. But, though the Taoist way must keep this in mind when addressing others, it also would have us live in the openness of ambiguity.
There are some whose behaviors are changing more than others. There are some who follow a path of personal transformation which, one would hope, would increase the ambiguity between our knowing and our not knowing of 'who' they are. A swimming coach would be less likely to assign a previous time-performance to a diligent trainee than to one who merely splashed about in the shallows.
Open-heartedness is the Taoist way. And though it can theoretically lead to injury, it is also the Taoist way to have no one who can be injured. Still, though the tiger finds no essential place in the sage to sink its teeth, the sage is careful not to give it the opportunity to existentially do so.
I trust this is all sufficiently ambiguous.
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